Such a facility is in particular known from document FR 2,352,573. It includes a lift pump, intended to transfer the aqueous phase/organic phase mixture toward a settler. The lift pump typically includes a stationary frustoconical stator in which a rotor rotates, made up of blades mounted on a shaft. The rotation of the rotor generates a rising of the liquid against the inner wall of the frustoconical stator. The mixture of liquids overflows toward an upper level of the facility and flows toward the settler.
A similar facility is known from document GB 793,025, which in particular describes a pump including a moving body rotatable along the vertical axis, said moving body defining a first frustoconical inner surface positioned along the vertical axis and upwardly flared.
In some cases, this type of pump is not fully satisfactory. A recent study has in particular shown significant shearing between the rotor and the stator. This phenomenon generates fine droplets that extend the settling time and increase the quantity of organic phase retained in the aqueous phase.